Fast cell setup for dual connectivity

ABSTRACT

Provided are a method for fast cell setup. According to an embodiment of the present disclosure, the method includes receiving a cell group configuration including a list of cells, performing measurement on the cells, identifying at least one invalid cell among the cells included in the cell group configuration based on a result of the measurement, reporting information on the identified invalid cell.

TECHNICAL FIELD

The present disclosure relates to dual connectivity.

BACKGROUND

Efforts have been made to develop an improved 5th-generation (5G)communication system or a pre-5G communication system in order tosatisfy a growing demand on radio data traffic after commercializationof a 4th-generation (4G) communication system. A standardization act fora 5G mobile communication standard work has been formally started in3GPP, and there is ongoing discussion in a standardization working groupunder a tentative name of a new radio access (NR).

Meanwhile, an upper layer protocol defines a protocol state toconsistently manage an operational state of a user equipment (UE), andindicates a function and procedure of the UE in detail. In thediscussion on the NR standardization, an RRC state is discussed suchthat an RRC_CONNECTED state and an RRC_IDLE state are basically defined,and an RRC_INACTIVE state is additionally introduced.

SUMMARY

In the prior art, there are some discussion to support fast cell setupfor MR-DC. It is argued that SCG lower layer configuration is kept whenthe UE initiate resume procedure, i.e. until the UE receive resumemessage including SCG configuration from the network.

The problem of the prior art is that when the network direct UE toadd/modify/resume SCell(s) by providing new SCell configuration orcommending to resume some of all SCell(s) in the stored SCellconfiguration, the SCell addition or SN(Secondary Node) addition by(re-)configuration or resume can be failed because the network doesn'tknow which cell(s) is valid in the UE at that time. Valid cell(s) in theUE can be vary over time (e.g. due to UE mobility) while all cells inthe SCG configuration are valid in the moment the UE transit state fromRRC connected mode to RRC inactive mode.

According to an embodiment of the present disclosure, a method performedby a wireless device in a wireless communication system is provided. Themethod may comprise receiving a cell group configuration including alist of cells, performing measurement on the cells, identifying at leastone invalid cell among the cells included in the cell groupconfiguration based on a result of the measurement, reportinginformation on the identified invalid cell.

The present disclosure can have various advantageous effects.

For example, a UE may perform efficient handling of radio bearer(s)associated to invalid SCell(s). In specific, fast cell setup may beachieved by excluding the invalid cells during the DC setup.

For example, it may be beneficial to prevent unnecessary triggering ofprocedure such as synchronization, Random access and transmission due totrial of transmission or reception via radio bearer(s) associated toinvalid SCell(s).

Advantageous effects which can be obtained through specific embodimentsof the present disclosure are not limited to the advantageous effectslisted above. For example, there may be a variety of technical effectsthat a person having ordinary skill in the related art can understandand/or derive from the present disclosure. Accordingly, the specificeffects of the present disclosure are not limited to those explicitlydescribed herein, but may include various effects that may be understoodor derived from the technical features of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows examples of 5G usage scenarios to which the technicalfeatures of the present disclosure can be applied.

FIG. 2 shows an example of a wireless communication system to which thetechnical features of the present disclosure can be applied.

FIG. 3 shows an example of a wireless communication system to which thetechnical features of the present disclosure can be applied.

FIG. 4 shows another example of a wireless communication system to whichthe technical features of the present disclosure can be applied.

FIG. 5 shows a block diagram of a user plane protocol stack to which thetechnical features of the present disclosure can be applied.

FIG. 6 shows a block diagram of a control plane protocol stack to whichthe technical features of the present disclosure can be applied.

FIG. 7 illustrates a data flow example in the 3GPP NR system.

FIG. 8 shows a method for fast failure reporting according to anembodiment of the present disclosure.

FIG. 9 shows a method for the fast failure reporting for invalidSCell(s) in RRC IDLE mode according to an embodiment of the presentdisclosure.

FIG. 10 shows a method for the fast failure reporting for invalidSCell(s) in RRC IDLE mode according to an embodiment of the presentdisclosure.

FIG. 11 shows a method for handling of radio bearer(s) associated toinvalid SCell(s) according to an embodiment of the present disclosure.

FIG. 12 shows a method for handling of radio bearer(s) associated toinvalid SCell(s) according to an embodiment of the present disclosure.

FIG. 13 shows more detailed wireless device to implement an embodimentof the present disclosure.

FIG. 14 shows an example of an AI device to which the technical featuresof the present disclosure can be applied.

FIG. 15 shows an example of an AI system to which the technical featuresof the present disclosure can be applied.

DETAILED DESCRIPTION

The technical features described below may be used by a communicationstandard by the 3rd generation partnership project (3GPP)standardization organization, a communication standard by the instituteof electrical and electronics engineers (IEEE), etc. For example, thecommunication standards by the 3GPP standardization organization includelong-term evolution (LTE) and/or evolution of LTE systems. The evolutionof LTE systems includes LTE-advanced (LTE-A), LTE-A Pro, and/or 5G newradio (NR). The communication standard by the IEEE standardizationorganization includes a wireless local area network (WLAN) system suchas IEEE 802.11a/b/g/n/ac/ax. The above system uses various multipleaccess technologies such as orthogonal frequency division multipleaccess (OFDMA) and/or single carrier frequency division multiple access(SC-FDMA) for downlink (DL) and/or uplink (UL). For example, only OFDMAmay be used for DL and only SC-FDMA may be used for UL. Alternatively,OFDMA and SC-FDMA may be used for DL and/or UL.

In this document, the term “/” and “,” should be interpreted to indicate“and/or.” For instance, the expression “A/B” may mean “A and/or B.”Further, “A, B” may mean “A and/or B.” Further, “AB/C” may mean “atleast one of A, B, and/or C.” Also, “A, B, C” may mean “at least one ofA, B, and/or C.”

Further, in the document, the term “or” should be interpreted toindicate “and/or.” For instance, the expression “A or B” may comprise 1)only A, 2) only B, and/or 3) both A and B. In other words, the term “or”in this document should be interpreted to indicate “additionally oralternatively.”

The following drawings are created to explain specific embodiments ofthe present disclosure. The names of the specific devices or the namesof the specific signals/messages/fields shown in the drawings areprovided by way of example, and thus the technical features of thepresent disclosure are not limited to the specific names used in thefollowing drawings.

FIG. 1 shows examples of 5G usage scenarios to which the technicalfeatures of the present disclosure can be applied.

The 5G usage scenarios shown in FIG. 1 are only exemplary, and thetechnical features of the present disclosure can be applied to other 5Gusage scenarios which are not shown in FIG. 1.

Referring to FIG. 1, the three main requirements areas of 5G include (1)enhanced mobile broadband (eMBB) domain, (2) massive machine typecommunication (mMTC) area, and (3) ultra-reliable and low latencycommunications (URLLC) area. Some use cases may require multiple areasfor optimization and, other use cases may only focus on only one keyperformance indicator (KPI). 5G is to support these various use cases ina flexible and reliable way.

eMBB focuses on across-the-board enhancements to the data rate, latency,user density, capacity and coverage of mobile broadband access. The eMBBaims ˜10 Gbps of throughput. eMBB far surpasses basic mobile Internetaccess and covers rich interactive work and media and entertainmentapplications in cloud and/or augmented reality. Data is one of the keydrivers of 5G and may not be able to see dedicated voice services forthe first time in the 5G era. In 5G, the voice is expected to beprocessed as an application simply using the data connection provided bythe communication system. The main reason for the increased volume oftraffic is an increase in the size of the content and an increase in thenumber of applications requiring high data rates. Streaming services(audio and video), interactive video and mobile Internet connectivitywill become more common as more devices connect to the Internet. Many ofthese applications require always-on connectivity to push real-timeinformation and notifications to the user. Cloud storage andapplications are growing rapidly in mobile communication platforms,which can be applied to both work and entertainment. Cloud storage is aspecial use case that drives growth of uplink data rate. 5G is also usedfor remote tasks on the cloud and requires much lower end-to-end delayto maintain a good user experience when the tactile interface is used.In entertainment, for example, cloud games and video streaming areanother key factor that increases the demand for mobile broadbandcapabilities. Entertainment is essential in smartphones and tabletsanywhere, including high mobility environments such as trains, cars andairplanes. Another use case is augmented reality and informationretrieval for entertainment. Here, augmented reality requires very lowlatency and instantaneous data amount.

mMTC is designed to enable communication between devices that arelow-cost, massive in number and battery-driven, intended to supportapplications such as smart metering, logistics, and field and bodysensors. mMTC aims ˜10 years on battery and/or ˜1 million devices/km2.mMTC allows seamless integration of embedded sensors in all areas and isone of the most widely used 5G applications. Potentially by 2020,internet-of-things (IoT) devices are expected to reach 20.4 billion.Industrial IoT is one of the areas where 5G plays a key role in enablingsmart cities, asset tracking, smart utilities, agriculture and securityinfrastructures.

URLLC will make it possible for devices and machines to communicate withultra-reliability, very low latency and high availability, making itideal for vehicular communication, industrial control, factoryautomation, remote surgery, smart grids and public safety applications.URLLC aims ˜1 ms of latency. URLLC includes new services that willchange the industry through links with ultra-reliability/low latency,such as remote control of key infrastructure and self-driving vehicles.The level of reliability and latency is essential for smart gridcontrol, industrial automation, robotics, drones control andcoordination.

Next, a plurality of use cases included in the triangle of FIG. 1 willbe described in more detail.

5G can complement fiber-to-the-home (FTTH) and cable-based broadband (orDOCSIS) as a means of delivering streams rated from hundreds of megabitsper second to gigabits per second. This high speed can be required todeliver TVs with resolutions of 4K or more (6K, 8K and above) as well asvirtual reality (VR) and augmented reality (AR). VR and AR applicationsinclude mostly immersive sporting events. Certain applications mayrequire special network settings. For example, in the case of a VR game,a game company may need to integrate a core server with an edge networkserver of a network operator to minimize delay.

Automotive is expected to become an important new driver for 5G, withmany use cases for mobile communications to vehicles. For example,entertainment for passengers demands high capacity and high mobilebroadband at the same time. This is because future users will continueto expect high-quality connections regardless of their location andspeed. Another use case in the automotive sector is an augmented realitydashboard. The driver can identify an object in the dark on top of whatis being viewed through the front window through the augmented realitydashboard. The augmented reality dashboard displays information thatwill inform the driver about the object's distance and movement. In thefuture, the wireless module enables communication between vehicles,information exchange between the vehicle and the supportinginfrastructure, and information exchange between the vehicle and otherconnected devices (e.g. devices accompanied by a pedestrian). The safetysystem allows the driver to guide the alternative course of action sothat he can drive more safely, thereby reducing the risk of accidents.The next step will be a remotely controlled vehicle or self-drivingvehicle. This requires a very reliable and very fast communicationbetween different self-driving vehicles and between vehicles andinfrastructure. In the future, a self-driving vehicle will perform alldriving activities, and the driver will focus only on traffic that thevehicle itself cannot identify. The technical requirements ofself-driving vehicles require ultra-low latency and high-speedreliability to increase traffic safety to a level not achievable byhumans.

Smart cities and smart homes, which are referred to as smart societies,will be embedded in high density wireless sensor networks. Thedistributed network of intelligent sensors will identify conditions forcost and energy-efficient maintenance of a city or house. A similarsetting can be performed for each home. Temperature sensors, windows andheating controllers, burglar alarms and appliances are all wirelesslyconnected. Many of these sensors typically require low data rate, lowpower and low cost. However, for example, real-time high-definition (HD)video may be required for certain types of devices for monitoring.

The consumption and distribution of energy, including heat or gas, ishighly dispersed, requiring automated control of distributed sensornetworks. The smart grid interconnects these sensors using digitalinformation and communication technologies to collect and act oninformation. This information can include supplier and consumerbehavior, allowing the smart grid to improve the distribution of fuel,such as electricity, in terms of efficiency, reliability, economy,production sustainability, and automated methods. The smart grid can beviewed as another sensor network with low latency.

The health sector has many applications that can benefit from mobilecommunications. Communication systems can support telemedicine toprovide clinical care in remote locations. This can help to reducebarriers to distance and improve access to health services that are notcontinuously available in distant rural areas. It is also used to savelives in critical care and emergency situations. Mobile communicationbased wireless sensor networks can provide remote monitoring and sensorsfor parameters such as heart rate and blood pressure.

Wireless and mobile communications are becoming increasingly importantin industrial applications. Wiring costs are high for installation andmaintenance. Thus, the possibility of replacing a cable with a wirelesslink that can be reconfigured is an attractive opportunity in manyindustries. However, achieving this requires that wireless connectionsoperate with similar delay, reliability, and capacity as cables and thattheir management is simplified. Low latency and very low errorprobabilities are new requirements that need to be connected to 5G.

Logistics and freight tracking are important use cases of mobilecommunications that enable tracking of inventory and packages anywhereusing location based information systems. Use cases of logistics andfreight tracking typically require low data rates, but require a largerange and reliable location information.

FIG. 2 shows an example of a wireless communication system to which thetechnical features of the present disclosure can be applied.

Referring to FIG. 2, the wireless communication system may include afirst device 210 and a second device 220.

The first device 210 includes a base station, a network node, atransmitting UE, a receiving UE, a wireless device, a wirelesscommunication device, a vehicle, a vehicle equipped with an autonomousdriving function, a connected car, a drone, an unmanned aerial vehicle(UAV), an artificial intelligence (AI) module, a robot, an AR device, aVR device, a mixed reality (MR) device, a hologram device, a publicsafety device, an MTC device, an IoT device, a medical device, afin-tech device (or, a financial device), a security device, aclimate/environmental device, a device related to 5G services, or adevice related to the fourth industrial revolution.

The second device 220 includes a base station, a network node, atransmitting UE, a receiving UE, a wireless device, a wirelesscommunication device, a vehicle, a vehicle equipped with an autonomousdriving function, a connected car, a drone, a UAV, an AI module, arobot, an AR device, a VR device, an MR device, a hologram device, apublic safety device, an MTC device, an IoT device, a medical device, afin-tech device (or, a financial device), a security device, aclimate/environmental device, a device related to 5G services, or adevice related to the fourth industrial revolution.

For example, the UE may include a mobile phone, a smart phone, a laptopcomputer, a digital broadcasting terminal, a personal digital assistant(PDA), a portable multimedia player (PMP), a navigation device, a slatepersonal computer (PC), a tablet PC, an ultrabook, a wearable device(e.g. a smartwatch, a smart glass, a head mounted display (HMD)) . Forexample, the HMD may be a display device worn on the head. For example,the HMD may be used to implement AR, VR and/or MR.

For example, the drone may be a flying object that is flying by a radiocontrol signal without a person boarding it. For example, the VR devicemay include a device that implements an object or background in thevirtual world. For example, the AR device may include a device thatimplements connection of an object and/or a background of a virtualworld to an object and/or a background of the real world. For example,the MR device may include a device that implements fusion of an objectand/or a background of a virtual world to an object and/or a backgroundof the real world. For example, the hologram device may include a devicethat implements a 360-degree stereoscopic image by recording and playingstereoscopic information by utilizing a phenomenon of interference oflight generated by the two laser lights meeting with each other, calledholography. For example, the public safety device may include a videorelay device or a video device that can be worn by the user's body. Forexample, the MTC device and the IoT device may be a device that do notrequire direct human intervention or manipulation. For example, the MTCdevice and the IoT device may include a smart meter, a vending machine,a thermometer, a smart bulb, a door lock and/or various sensors. Forexample, the medical device may be a device used for the purpose ofdiagnosing, treating, alleviating, handling, or preventing a disease.For example, the medical device may be a device used for the purpose ofdiagnosing, treating, alleviating, or correcting an injury or disorder.For example, the medical device may be a device used for the purpose ofinspecting, replacing or modifying a structure or function. For example,the medical device may be a device used for the purpose of controllingpregnancy. For example, the medical device may include a treatmentdevice, a surgical device, an (in vitro) diagnostic device, a hearingaid and/or a procedural device, etc. For example, a security device maybe a device installed to prevent the risk that may occur and to maintainsafety. For example, the security device may include a camera, aclosed-circuit TV (CCTV), a recorder, or a black box. For example, thefin-tech device may be a device capable of providing financial servicessuch as mobile payment. For example, the fin-tech device may include apayment device or a point of sales (POS). For example, theclimate/environmental device may include a device for monitoring orpredicting the climate/environment.

The first device 210 may include at least one or more processors, suchas a processor 211, at least one memory, such as a memory 212, and atleast one transceiver, such as a transceiver 213. The processor 211 mayperform the functions, procedures, and/or methods of the presentdisclosure described below. The processor 211 may perform one or moreprotocols. For example, the processor 211 may perform one or more layersof the air interface protocol. The memory 212 is connected to theprocessor 211 and may store various types of information and/orinstructions. The transceiver 213 is connected to the processor 211 andmay be controlled to transmit and receive wireless signals.

The second device 220 may include at least one or more processors, suchas a processor 221, at least one memory, such as a memory 222, and atleast one transceiver, such as a transceiver 223. The processor 221 mayperform the functions, procedures, and/or methods of the presentdisclosure described below. The processor 221 may perform one or moreprotocols. For example, the processor 221 may perform one or more layersof the air interface protocol. The memory 222 is connected to theprocessor 221 and may store various types of information and/orinstructions. The transceiver 223 is connected to the processor 221 andmay be controlled to transmit and receive wireless signals.

The memory 212, 222 may be connected internally or externally to theprocessor 211, 212, or may be connected to other processors via avariety of technologies such as wired or wireless connections.

The first device 210 and/or the second device 220 may have more than oneantenna. For example, antenna 214 and/or antenna 224 may be configuredto transmit and receive wireless signals.

FIG. 3 shows an example of a wireless communication system to which thetechnical features of the present disclosure can be applied.

Specifically, FIG. 3 shows a system architecture based on anevolved-UMTS terrestrial radio access network (E-UTRAN). Theaforementioned LTE is a part of an evolved-UTMS (e-UMTS) using theE-UTRAN.

Referring to FIG. 3, the wireless communication system includes one ormore user equipment (UE) 310, an E-UTRAN and an evolved packet core(EPC). The UE 310 refers to a communication equipment carried by a user.The UE 310 may be fixed or mobile. The UE 310 may be referred to asanother terminology, such as a mobile station (MS), a user terminal(UT), a subscriber station (SS), a wireless device, etc.

The E-UTRAN consists of one or more evolved NodeB (eNB) 320. The eNB 320provides the E-UTRA user plane and control plane protocol terminationstowards the UE 10. The eNB 320 is generally a fixed station thatcommunicates with the UE 310. The eNB 320 hosts the functions, such asinter-cell radio resource management (RRM), radio bearer (RB) control,connection mobility control, radio admission control, measurementconfiguration/provision, dynamic resource allocation (scheduler), etc.The eNB 320 may be referred to as another terminology, such as a basestation (BS), a base transceiver system (BTS), an access point (AP),etc.

A downlink (DL) denotes communication from the eNB 320 to the UE 310. Anuplink (UL) denotes communication from the UE 310 to the eNB 320. Asidelink (SL) denotes communication between the UEs 310. In the DL, atransmitter may be a part of the eNB 320, and a receiver may be a partof the UE 310. In the UL, the transmitter may be a part of the UE 310,and the receiver may be a part of the eNB 320. In the SL, thetransmitter and receiver may be a part of the UE 310.

The EPC includes a mobility management entity (MME), a serving gateway(S-GW) and a packet data network (PDN) gateway (P-GW). The MME hosts thefunctions, such as non-access stratum (NAS) security, idle statemobility handling, evolved packet system (EPS) bearer control, etc. TheS-GW hosts the functions, such as mobility anchoring, etc. The S-GW is agateway having an E-UTRAN as an endpoint. For convenience, MME/S-GW 330will be referred to herein simply as a “gateway,” but it is understoodthat this entity includes both the MME and S-GW. The P-GW hosts thefunctions, such as UE Internet protocol (IP) address allocation, packetfiltering, etc. The P-GW is a gateway having a PDN as an endpoint. TheP-GW is connected to an external network.

The UE 310 is connected to the eNB 320 by means of the Uu interface. TheUEs 310 are interconnected with each other by means of the PC5interface. The eNBs 320 are interconnected with each other by means ofthe X2 interface. The eNBs 320 are also connected by means of the S1interface to the EPC, more specifically to the MME by means of theS1-MME interface and to the S-GW by means of the S1-U interface. The S1interface supports a many-to-many relation between MMEs/S-GWs and eNB s.

FIG. 4 shows another example of a wireless communication system to whichthe technical features of the present disclosure can be applied.

Specifically, FIG. 4 shows a system architecture based on a 5G NR. Theentity used in the 5G NR (hereinafter, simply referred to as “NR”) mayabsorb some or all of the functions of the entities introduced in FIG. 3(e.g. eNB, MME, S-GW). The entity used in the NR may be identified bythe name “NG” for distinction from the LTE/LTE-A.

Referring to FIG. 4, the wireless communication system includes one ormore UE 410, a next-generation RAN (NG-RAN) and a 5th generation corenetwork (5GC). The NG-RAN consists of at least one NG-RAN node. TheNG-RAN node is an entity corresponding to the eNB 320 shown in FIG. 3.The NG-RAN node consists of at least one gNB 421 and/or at least oneng-eNB 422. The gNB 421 provides NR user plane and control planeprotocol terminations towards the UE 410. The ng-eNB 422 provides E-UTRAuser plane and control plane protocol terminations towards the UE 410.

The 5GC includes an access and mobility management function (AMF), auser plane function (UPF) and a session management function (SMF). TheAMF hosts the functions, such as NAS security, idle state mobilityhandling, etc. The AMF is an entity including the functions of theconventional MME. The UPF hosts the functions, such as mobilityanchoring, protocol data unit (PDU) handling. The UPF an entityincluding the functions of the conventional S-GW. The SMF hosts thefunctions, such as UE IP address allocation, PDU session control.

The gNBs 421 and ng-eNBs 422 are interconnected with each other by meansof the Xn interface. The gNBs 421 and ng-eNBs 422 are also connected bymeans of the NG interfaces to the 5GC, more specifically to the AMF bymeans of the NG-C interface and to the UPF by means of the NG-Uinterface.

A protocol structure between network entities described above isdescribed. On the system of FIG. 3 and/or FIG. 4, layers of a radiointerface protocol between the UE and the network (e.g. NG-RAN and/orE-UTRAN) may be classified into a first layer (L1), a second layer (L2),and a third layer (L3) based on the lower three layers of the opensystem interconnection (OSI) model that is well-known in thecommunication system.

FIG. 5 shows a block diagram of a user plane protocol stack to which thetechnical features of the present disclosure can be applied. FIG. 6shows a block diagram of a control plane protocol stack to which thetechnical features of the present disclosure can be applied.

The user/control plane protocol stacks shown in FIG. 5 and FIG. 6 areused in NR. However, user/control plane protocol stacks shown in FIG. 5and FIG. 6 may be used in LTE/LTE-A without loss of generality, byreplacing gNB/AMF with eNB/MME.

Referring to FIG. 5 and FIG. 6, a physical (PHY) layer belonging to L1.The PHY layer offers information transfer services to media accesscontrol (MAC) sublayer and higher layers. The PHY layer offers to theMAC sublayer transport channels. Data between the MAC sublayer and thePHY layer is transferred via the transport channels. Between differentPHY layers, i.e., between a PHY layer of a transmission side and a PHYlayer of a reception side, data is transferred via the physicalchannels.

The MAC sublayer belongs to L2. The main services and functions of theMAC sublayer include mapping between logical channels and transportchannels, multiplexing/de-multiplexing of MAC service data units (SDUs)belonging to one or different logical channels into/from transportblocks (TB) delivered to/from the physical layer on transport channels,scheduling information reporting, error correction through hybridautomatic repeat request (HARD), priority handling between UEs by meansof dynamic scheduling, priority handling between logical channels of oneUE by means of logical channel prioritization (LCP), etc. The MACsublayer offers to the radio link control (RLC) sublayer logicalchannels.

The RLC sublayer belong to L2. The RLC sublayer supports threetransmission modes, i.e. transparent mode (TM), unacknowledged mode(UM), and acknowledged mode (AM), in order to guarantee various qualityof services (QoS) required by radio bearers. The main services andfunctions of the RLC sublayer depend on the transmission mode. Forexample, the RLC sublayer provides transfer of upper layer PDUs for allthree modes, but provides error correction through ARQ for AM only. InLTE/LTE-A, the RLC sublayer provides concatenation, segmentation andreassembly of RLC SDUs (only for UM and AM data transfer) andre-segmentation of RLC data PDUs (only for AM data transfer). In NR, theRLC sublayer provides segmentation (only for AM and UM) andre-segmentation (only for AM) of RLC SDUs and reassembly of SDU (onlyfor AM and UM). That is, the NR does not support concatenation of RLCSDUs. The RLC sublayer offers to the packet data convergence protocol(PDCP) sublayer RLC channels.

The PDCP sublayer belong to L2. The main services and functions of thePDCP sublayer for the user plane include header compression anddecompression, transfer of user data, duplicate detection, PDCP PDUrouting, retransmission of PDCP SDUs, ciphering and deciphering, etc.The main services and functions of the PDCP sublayer for the controlplane include ciphering and integrity protection, transfer of controlplane data, etc.

The service data adaptation protocol (SDAP) sublayer belong to L2. TheSDAP sublayer is only defined in the user plane. The SDAP sublayer isonly defined for NR. The main services and functions of SDAP include,mapping between a QoS flow and a data radio bearer (DRB), and markingQoS flow ID (QFI) in both DL and UL packets. The SDAP sublayer offers to5GC QoS flows.

A radio resource control (RRC) layer belongs to L3. The RRC layer isonly defined in the control plane. The RRC layer controls radioresources between the UE and the network. To this end, the RRC layerexchanges RRC messages between the UE and the BS. The main services andfunctions of the RRC layer include broadcast of system informationrelated to AS and NAS, paging, establishment, maintenance and release ofan RRC connection between the UE and the network, security functionsincluding key management, establishment, configuration, maintenance andrelease of radio bearers, mobility functions, QoS management functions,UE measurement reporting and control of the reporting, NAS messagetransfer to/from NAS from/to UE.

In other words, the RRC layer controls logical channels, transportchannels, and physical channels in relation to the configuration,reconfiguration, and release of radio bearers. A radio bearer refers toa logical path provided by L1 (PHY layer) and L2 (MAC/RLC/PDCP/SDAPsublayer) for data transmission between a UE and a network. Setting theradio bearer means defining the characteristics of the radio protocollayer and the channel for providing a specific service, and setting eachspecific parameter and operation method. Radio bearer may be dividedinto signaling RB (SRB) and data RB (DRB). The SRB is used as a path fortransmitting RRC messages in the control plane, and the DRB is used as apath for transmitting user data in the user plane.

An RRC state indicates whether an RRC layer of the UE is logicallyconnected to an RRC layer of the E-UTRAN. In LTE/LTE-A, when the RRCconnection is established between the RRC layer of the UE and the RRClayer of the E-UTRAN, the UE is in the RRC connected state(RRC_CONNECTED). Otherwise, the UE is in the RRC idle state (RRC_IDLE).In NR, the RRC inactive state (RRC_INACTIVE) is additionally introduced.RRC_INACTIVE may be used for various purposes. For example, the massivemachine type communications (MMTC) UEs can be efficiently managed inRRC_INACTIVE. When a specific condition is satisfied, transition is madefrom one of the above three states to the other.

A predetermined operation may be performed according to the RRC state.In RRC_IDLE, public land mobile network (PLMN) selection, broadcast ofsystem information (SI), cell re-selection mobility, core network (CN)paging and discontinuous reception (DRX) configured by NAS may beperformed. The UE shall have been allocated an identifier (ID) whichuniquely identifies the UE in a tracking area. No RRC context stored inthe BS.

In RRC_CONNECTED, the UE has an RRC connection with the network (i.e.E-UTRAN/NG-RAN). Network-CN connection (both C/U-planes) is alsoestablished for UE. The UE AS context is stored in the network and theUE. The RAN knows the cell which the UE belongs to. The network cantransmit and/or receive data to/from UE. Network controlled mobilityincluding measurement is also performed.

Most of operations performed in RRC_IDLE may be performed inRRC_INACTIVE. But, instead of CN paging in RRC_IDLE, RAN paging isperformed in RRC_INACTIVE. In other words, in RRC_IDLE, paging formobile terminated (MT) data is initiated by core network and paging areais managed by core network. In RRC_INACTIVE, paging is initiated byNG-RAN, and RAN-based notification area (RNA) is managed by NG-RAN.Further, instead of DRX for CN paging configured by NAS in RRC_IDLE, DRXfor RAN paging is configured by NG-RAN in RRC_INACTIVE. Meanwhile, inRRC_INACTIVE, 5GC-NG-RAN connection (both C/U-planes) is established forUE, and the UE AS context is stored in NG-RAN and the UE. NG-RAN knowsthe RNA which the UE belongs to.

NAS layer is located at the top of the RRC layer. The NAS controlprotocol performs the functions, such as authentication, mobilitymanagement, security control.

The physical channels may be modulated according to OFDM processing andutilizes time and frequency as radio resources. The physical channelsconsist of a plurality of orthogonal frequency division multiplexing(OFDM) symbols in time domain and a plurality of subcarriers infrequency domain. One subframe consists of a plurality of OFDM symbolsin the time domain. A resource block is a resource allocation unit, andconsists of a plurality of OFDM symbols and a plurality of subcarriers.In addition, each subframe may use specific subcarriers of specific OFDMsymbols (e.g. first OFDM symbol) of the corresponding subframe for aphysical downlink control channel (PDCCH), i.e. L1/L2 control channel. Atransmission time interval (TTI) is a basic unit of time used by ascheduler for resource allocation. The TTI may be defined in units ofone or a plurality of slots, or may be defined in units of mini-slots.

The transport channels are classified according to how and with whatcharacteristics data are transferred over the radio interface. DLtransport channels include a broadcast channel (BCH) used fortransmitting system information, a downlink shared channel (DL-SCH) usedfor transmitting user traffic or control signals, and a paging channel(PCH) used for paging a UE. UL transport channels include an uplinkshared channel (UL-SCH) for transmitting user traffic or control signalsand a random access channel (RACH) normally used for initial access to acell.

Different kinds of data transfer services are offered by MAC sublayer.Each logical channel type is defined by what type of information istransferred. Logical channels are classified into two groups: controlchannels and traffic channels.

Control channels are used for the transfer of control plane informationonly. The control channels include a broadcast control channel (BCCH), apaging control channel (PCCH), a common control channel (CCCH) and adedicated control channel (DCCH). The BCCH is a DL channel forbroadcasting system control information. The PCCH is DL channel thattransfers paging information, system information change notifications.The CCCH is a channel for transmitting control information between UEsand network. This channel is used for UEs having no RRC connection withthe network. The DCCH is a point-to-point bi-directional channel thattransmits dedicated control information between a UE and the network.This channel is used by UEs having an RRC connection.

Traffic channels are used for the transfer of user plane informationonly. The traffic channels include a dedicated traffic channel (DTCH).The DTCH is a point-to-point channel, dedicated to one UE, for thetransfer of user information. The DTCH can exist in both UL and DL.

Regarding mapping between the logical channels and transport channels,in DL, BCCH can be mapped to BCH, BCCH can be mapped to DL-SCH, PCCH canbe mapped to PCH, CCCH can be mapped to DL-SCH, DCCH can be mapped toDL-SCH, and DTCH can be mapped to DL-SCH. In UL, CCCH can be mapped toUL-SCH, DCCH can be mapped to UL-SCH, and DTCH can be mapped to UL-SCH.

NR supports multiple numerology (or, subcarrier spacing (SCS)) tosupport various 5G services. For example, when the SCS is 15 kHz, widearea in traditional cellular bands may be supported. When the SCS is 30kHz/60 kHz, dense-urban, lower latency and wider carrier bandwidth maybe supported. When the SCS is 60 kHz or higher, a bandwidth greater than24.25 GHz may be supported to overcome phase noise.

The NR frequency band may be defined as two types of frequency range,i.e., FR1 and FR2. The numerical value of the frequency range may bechanged. For example, the frequency ranges of the two types (FR1 andFR2) may be as shown in Table 1 below. For ease of explanation, in thefrequency ranges used in the NR system, FR1 may mean “sub 6 GHz range”,FR2 may mean “above 6 GHz range,” and may be referred to as millimeterwave (mmW).

TABLE 1 Frequency Range Corresponding Subcarrier designation frequencyrange Spacing FR1  450 MHz-6000 MHz 15, 30, 60 kHz FR2 24250 MHz-52600MHz 60, 120, 240 kHz

As mentioned above, the numerical value of the frequency range of the NRsystem may be changed. For example, FR1 may include a frequency band of410 MHz to 7125 MHz as shown in Table 2 below. That is, FR1 may includea frequency band of 6 GHz (or 5850, 5900, 5925 MHz, etc.) or more. Forexample, a frequency band of 6 GHz (or 5850, 5900, 5925 MHz, etc.) ormore included in FR1 may include an unlicensed band. Unlicensed bandsmay be used for a variety of purposes, for example for communication forvehicles (e.g., autonomous driving).

TABLE 2 Frequency Range Corresponding Subcarrier designation frequencyrange Spacing FR1  410 MHz-7125 MHz 15, 30, 60 kHz FR2 24250 MHz-52600MHz 60, 120, 240 kHz

In the 3GPP NR system, RBs are classified into CRBs and physicalresource blocks (PRBs). CRBs are numbered from 0 and upwards in thefrequency domain for subcarrier spacing configuration u. The center ofsubcarrier 0 of CRB 0 for subcarrier spacing configuration u coincideswith ‘point A’ which serves as a common reference point for resourceblock grids. In the 3GPP NR system, PRBs are defined within a bandwidthpart (BWP) and numbered from 0 to NsizeBWP,i-1, where i is the number ofthe bandwidth part. The relation between the physical resource blocknPRB in the bandwidth part i and the common resource block nCRB is asfollows: nPRB=nCRB+NsizeBWP,i, where NsizeBWP,i is the common resourceblock where bandwidth part starts relative to CRB 0. The BWP includes aplurality of consecutive RBs. A carrier may include a maximum of N(e.g., 5) BWPs. A UE may be configured with one or more BWPs on a givencomponent carrier. Only one BWP among BWPs configured to the UE canactive at a time. The active BWP defines the UE's operating bandwidthwithin the cell's operating bandwidth.

In the present disclosure, the term “cell” may refer to a geographicarea to which one or more nodes provide a communication system, or referto radio resources. A “cell” of a geographic area may be understood ascoverage within which a node can provide service using a carrier and a“cell” as radio resources (e.g. time-frequency resources) is associatedwith bandwidth (BW) which is a frequency range configured by thecarrier. The “cell” associated with the radio resources is defined by acombination of downlink resources and uplink resources, for example, acombination of a downlink (DL) component carrier (CC) and a uplink (UL)CC. The cell may be configured by downlink resources only, or may beconfigured by downlink resources and uplink resources. Since DLcoverage, which is a range within which the node is capable oftransmitting a valid signal, and UL coverage, which is a range withinwhich the node is capable of receiving the valid signal from the UE,depends upon a carrier carrying the signal, the coverage of the node maybe associated with coverage of the “cell” of radio resources used by thenode. Accordingly, the term “cell” may be used to represent servicecoverage of the node sometimes, radio resources at other times, or arange that signals using the radio resources can reach with validstrength at other times.

In carrier aggregation (CA), two or more CCs are aggregated. A UE maysimultaneously receive or transmit on one or multiple CCs depending onits capabilities. CA is supported for both contiguous and non-contiguousCCs. When CA is configured the UE only has one radio resource control(RRC) connection with the network. At RRC connectionestablishment/re-establishment/handover, one serving cell provides thenon-access stratum (NAS) mobility information, and at RRC connectionre-establishment/handover, one serving cell provides the security input.This cell is referred to as the Primary Cell (PCell). The PCell is acell, operating on the primary frequency, in which the UE eitherperforms the initial connection establishment procedure or initiates theconnection re-establishment procedure. Depending on UE capabilities,Secondary Cells (SCells) can be configured to form together with thePCell a set of serving cells. A SCell is a cell providing additionalradio resources on top of Special Cell. The configured set of servingcells for a UE therefore always consists of one PCell and one or moreSCells. For dual connectivity operation, the term Special Cell (SpCell)refers to the PCell of the master cell group (MCG) or the PSCell of thesecondary cell group (SCG). An SpCell supports PUCCH transmission andcontention-based random access, and is always activated. The MCG is agroup of serving cells associated with a master node, comprising of theSpCell (PCell) and optionally one or more SCells. The SCG is the subsetof serving cells associated with a secondary node, comprising of thePSCell and zero or more SCells, for a UE configured with dualconnectivity (DC). For a UE in RRC_CONNECTED not configured with CA/DCthere is only one serving cell comprising of the PCell. For a UE inRRC_CONNECTED configured with CA/DC the term “serving cells” is used todenote the set of cells comprising of the SpCell(s) and all SCells. InDC, two MAC entities are configured in a UE: one for the MCG and one forthe SCG.

FIG. 7 illustrates a data flow example in the 3GPP NR system.

In FIG. 7, “RB” denotes a radio bearer, and “H” denotes a header. Radiobearers are categorized into two groups: data radio bearers (DRB) foruser plane data and signalling radio bearers (SRB) for control planedata. The MAC PDU is transmitted/received using radio resources throughthe PHY layer to/from an external device. The MAC PDU arrives to the PHYlayer in the form of a transport block.

In the PHY layer, the uplink transport channels UL-SCH and RACH aremapped to their physical channels PUSCH and PRACH, respectively, and thedownlink transport channels DL-SCH, BCH and PCH are mapped to PDSCH,PBCH and PDSCH, respectively. In the PHY layer, uplink controlinformation (UCI) is mapped to PUCCH, and downlink control information(DCI) is mapped to PDCCH. A MAC PDU related to UL-SCH is transmitted bya UE via a PUSCH based on an UL grant, and a MAC PDU related to DL-SCHis transmitted by a BS via a PDSCH based on a DL assignment.

In the prior art, the UE may be configured to perform failureinformation procedure to report RLC failure of type duplication and (NR)SCG failure information to report SCG radio link failure.

According to the prior art, some examples of failure informationprocedure and SCG failure information may be performed as follows.

In case of DC, the UE shall:

1> upon T313 expiry; or

1> upon random access problem indication from SCG MAC; or

1> upon indication from SCG RLC, which is allowed to be sent on PSCell,that the maximum number of retransmissions has been reached for an SCGor split DRB:

2> consider radio link failure to be detected for the SCG i.e. SCG-RLF;

2> initiate the SCG failure information procedure to report SCG radiolink failure;

In case of CA PDCP duplication, the UE shall:

1> upon indication from an RLC entity, which is restricted to be sent onSCell only, that the maximum number of retransmissions has been reached:

2> initiate the failure information procedure to report RLC failure oftype duplication;

In the priori art, the UE performs IDLE mode measurement in RRC_IDLE butit can be applied in RRC inactive mode. Then, the UE perform measurementfor SCell(s) in RRC inactive mode and identify whether SCell is valid ornot based on measurements.

In the prior art, there are some discussion to support fast cell setupfor MR-DC. It is argued that SCG lower layer configuration is kept whenthe UE initiate resume procedure, i.e. until the UE receive resumemessage including SCG configuration from the network.

The problem of the prior art is that when the network direct UE toadd/modify/resume SCell(s) by providing new SCell configuration orcommending to resume some of all SCell(s) in the stored SCellconfiguration, the SCell addition or SN(Secondary Node) addition by(re-)configuration or resume can be failed because the network doesn'tknow which cell(s) is valid in the UE at that time. Valid cell(s) in theUE can be vary over time (e.g. due to UE mobility) while all cells inthe SCG configuration are valid in the moment the UE transit state fromRRC connected mode to RRC inactive mode.

According to the prior art, regardless of whether the cells which thenetwork direct UE to add/modify/resume is valid or not, the UE shallperform the direction of the network. However, the direction for theinvalid cell(s) is failed. The failure can be happen in middle of‘synchronization’ or ‘RA procedure’ or ‘UL transmission’. For exampleabout ‘synchronization’, the UE receives “out-of-sync” indications fromphysical layer and then, trigger failure information procedure or SCGfailure information procedure. But, it takes some time until the UEreceives “out-of-sync” indications from physical layer. The latency forcell setup will increase according to the prior art.

In this disclosure, it may be assumed that UE keeps SCG lower layerconfiguration when the UE initiate resume procedure. In specific, theSCG lower layer configuration may consist of PSCell configuration andSCell configuration. The UE may keep only PSCell configuration, or keepall configuration of PSCell configuration and SCell configuration. TheUE may keep configuration of some SCells but not keep one of someSCells. The configuration will be kept may be determined or(pre)configured by the network. The information for which configurationwill be kept may be provided to the UE in RRC (connection) releasemessage when the network make the UE in RRC connected mode to RRCinactive mode.

In this disclosure, a UE in inactive condition is at least a UE inRRC_INACTIVE in NR, in lightweight connection in LTE, suspended stated,or in RRC_INACTIVE or lightweight connection in eLTE. A RAN node is atleast gNB in NR, eNB in LTE or eNB in eLTE. In addition, the MN and SNconfigured with DC have at least combination of NR and NR, E-UTRAN andE-UTRAN, NR and E-UTRAN or E-UTRAN and NR.

Further, it may be assumed that UE keeps MCG SCell configuration whenthe UE initiate resume procedure. In specific, the UE may keepconfiguration of either all SCells or some SCells in MCG configuration.The configuration will be kept may be determined or (pre)configured bythe network. The information for which configuration will be kept may beprovided to the UE in RRC (connection) release message when the networkmake the UE in RRC connected mode to RRC inactive mode. The network mayperform MCG SCell and/or SCG configuration either blindly or based oninformation from the UE.

In this disclosure, a selective resumption of DC configuration may beone of the following types:

-   -   Type A: A resumption of the entire DC configuration    -   Type B: A resumption of the MCG configuration (selective        resuming of entire MCG configuration and/or selective resuming        for each SCells in the MCG)    -   Type C: A resumption of the SCG configuration (selective        resuming of entire SCG configuration and/or selective resuming        for each cells in the SCG)

To support above selective resumption of DC configuration while ininactive condition, the UE may receive a specific criteria from thenetwork for validity check of each DC configuration, e.g., the entire DCconfiguration, the entire or respective Scells in MCG or the entire orrespective cells in SCG. In other words, if the specific criteria aremet described below, the UE may consider each DC configuration valid. Aspecific criteria are as follows.

Option 1) The RAN node provides validity area information in which theeach DC configuration is considered valid. The validity area informationconsists of a cell or a list of cells. Additionally, for each DCconfiguration, the associated validity area information is provided. Theexamples of validity area information associated with each DCconfiguration are as follows.

-   -   A cell or a list of cells in which the entire DC configuration        is valid    -   A cell or a list of cells in which the entire MCG configuration        is valid    -   A cell or a list of cells in which the each SCells in the MCG is        valid    -   A cell or a list of cells in which the entire SCG configuration        is valid    -   A cell or a list of cells in which the each cells in the SCG is        valid

Option 2) The RAN node may provide a specific RSRP threshold with whicheach DC configuration is considered valid. If each cell of DCconfiguration is greater than or equal to the threshold value, the cellmay be considered to be valid. Optionally, the threshold value may beprovided for each DC configuration so that different threshold value isapplied to different cell/cell group. The examples of relation betweenthe threshold values and each DC configuration may be as follows.

-   -   The RSRP threshold for validation of the entire MCG        configuration. In this case, only if the cell quality of all the        cells in MCG is greater than or equal to the threshold, the UE        considers the MCG configuration valid.    -   The RSRP threshold per cell for validation of the each SCells in        the MCG.    -   The RSRP threshold for validation of the entire SCG        configuration. In this case, only if the cell quality of all the        cells in SCG is greater than or equal to the threshold, the UE        considers the SCG configuration valid.    -   The RSRP threshold per cell for validation of the each cells in        the SCG.

Option 2) The RAN node may provide a validity time duration in which theeach DC configuration is considered valid. Optionally, the validity timeand associated DC configuration may be provided. The examples ofrelation between the validity time and associated DC configuration maybe shown below.

-   -   Time duration during which the entire DC configuration is valid    -   Time duration during which the entire MCG configuration is valid    -   Time duration during which the entire SCG configuration is valid    -   Timer duration during which cell is valid in each DC        configuration    -   The RAN node provide validity timer value to calculate the        validity time duration.

Regarding the validity time duration, the UE may set validity timer withprovided the validity timer value to check validity of each DCconfiguration. The UE may start the validity timer when entering intoRRC inactive mode. If the validity timer is expired, the UE may considercorresponding configuration or cell is invalid.

The UE receives above criteria via a dedicated signaling or broadcastsignaling. When the UE configured with DC receives the command for statetransition to inactive condition, the UE receives the criteria viadedicated signaling. While in inactive condition, the UE receives thecriteria via broadcast e.g. system information message.

If the UE does not receive a specific criteria, the UE may use thereceived Cell Reselection Criteria used for reselection while inRRC_IDLE. According to the Cell Reselection Criteria, the UE may performcell reselection. If the UE is camped on the cell of the DCconfiguration, the UE may consider the cell is valid. The UE may performvalidity check for TA(Timing Advance), that is, whether Timing Advanceis valid or not. The UE may consider that TA for the cell is not valid,when the timeAlignmentTimer associated with the TAG to which this(Serving) Cell belongs is not running; or the timeAlignmentTimerassociated with the TAG to which this (Serving) Cell belongs is expired;or It is assumed the timeAlignmentTimer is running in RRC inactive

If the each DC configuration meets the criteria provided by the network,if any, the UE may include an indicator of whether the each DCconfiguration is valid based on a criteria in the message used for RRCconnection activation.

If the each DC configuration does not meet the criteria provided by thenetwork, if any, the UE may include an indicator of whether the each DCconfiguration is not valid based on a criteria in the message used forRRC connection activation.

If the each DC configuration does not meet the criteria provided by thenetwork, if any, the UE may release the each DC configuration that doesnot meet the criteria, and include an indicator of whether the each DCconfiguration is deleted or not in the message used for RRC connectionactivation. The deleted cells/cell group or kept cells/cell group isprovided to the network.

The RAN node that received the message from the UE may perform SNrelease or SN modification procedure based on an indicator.

Meanwhile, Data unit(s) (e.g. PDCP SDU, PDCP PDU, RLC SDU, RLC PDU, RLCSDU, MAC SDU, MAC CE, MAC PDU) in the present disclosure may betransmitted/received on a physical channel (e.g. PDSCH, PUSCH) based onresource allocation (e.g. UL grant, DL assignment). In the presentdisclosure, uplink resource allocation may be also referred to as uplinkgrant, and downlink resource allocation is also referred to as downlinkassignment. The resource allocation may include time domain resourceallocation and frequency domain resource allocation. In the presentdisclosure, an uplink grant may be either received by the UE dynamicallyon PDCCH, in a Random Access Response, or configured to the UEsemi-persistently by RRC. In the present disclosure, downlink assignmentmay be either received by the UE dynamically on the PDCCH, or configuredto the UE semi-persistently by RRC signaling from the BS.

FIG. 8 shows a method for fast failure reporting according to anembodiment of the present disclosure. A wireless device may communicatewith at least one of a mobile terminal, a network or autonomous vehiclesother than the wireless device.

In step S802, the wireless device may receive a cell group configurationincluding a list of cells. The cell group configuration may furtherinclude a measurement configuration for the measurement

In step S804, the wireless device may perform measurement on the cells.The measurement may be performed while the wireless device is in radioresource control (RRC) inactive state or a RRC idle state.

In step S806, the wireless device may identify at least one invalid cellamong the cells included in the cell group configuration based on atleast one of a result of the measurement. The invalid cells may beidentified based on a channel quality, a predefined validity area,timing advance (TA), or validity timer.

Further, the wireless device may be further configured to suspend aradio bearer which is related to the identified invalid cell. Thesuspending the radio bearer may bes performed when all cells related tothe radio bearer are invalid. In this case, the all cells related to theradio bearer may be a secondary cell (SCell). Meanwhile, the suspendingthe radio bearer may be performed when at least one cell related to theradio bearer is invalid. In this case, the at least one cell related tothe radio bearer may be a primary secondary cell (PSCell)

In step S808, the wireless device may report information on theidentified invalid cell. The information on the identified invalid cellmay include information of the suspended radio bearer.

According to embodiments of the present disclosure, a UE may performfast failure reporting for invalid SCell(s) as soon as identifyinginvalid SCell(s) without waiting of existing failure triggering.Further, the network may perform fast cell setup for CA and DCconfiguration by reducing latency for failure reporting including updateSCell information.

According to an embodiment of the present disclosure, a UE may performIDLE mode measurement in RRC inactive mode or RRC_IDLE mode. If the UEreceives message including SCell configuration and/or indication toresume all or some SCell(s) in the stored SCell configuration from thenetwork, the UE may comply the message, but the UE may identify all orsome SCell(s) in the SCell configuration or the stored SCellconfiguration is (or are) invalid. Then, the UE may immediatelyperform/initiate procedure to inform the network of the failure reason.The failure reason may be that SCell(s) is invalid where the procedurecan be either failure information procedure or SCG failure informationprocedure depending on failure reason, or new procedure. The list of theinvalid SCell(s) and valid SCell(s) may be included in the message. Uponreceiving them, the network may determine new SCell(s) among the validSCell(s) and provides message including new SCell configuration and/orIE to resume SCell(s) in the stored SCell configuration based on thedetermined new SCell(s) to the UE.

FIG. 9 shows a method for the fast failure reporting for invalidSCell(s) in RRC IDLE mode according to an embodiment of the presentdisclosure. In this embodiment, a UE may be not only a terminal device,but also any types of device operating as wireless device, for example,an integrated access backhaul (IAB) node. Therefore, a UE may bereferred as a wireless device. In this embodiment, a network may be atleast one of base station (BS), gNodeB (gNB) or eNodeB (eNB). In thisembodiment, it may be assumed that the UE supports dual connectivitywith a master node (MN) and a secondary node (SN). The MN may be a MgNBor MeNB, and the SN may be a SgNB or SeNB.

In step S902, the network may transmit configuration for idle statemeasurement (measIdleConfig) and validity criteria for SCell(s) to theUE. The validity criteria may be provided by the network via systeminformation or dedicated signaling. The dedicated signaling may be a RRCrelease message. When the UE receives the RRC release message, the UEmay enter into RRC inactive mode.

The valid cell may be a cell which satisfies at least one condition thatRSRP or RSRQ of the cell is greater than certain threshold and/or thatvalidity timer is running; and/or that the cell is belong to validityarea; and/or that TA of the cell is valid.

In step S904, upon receiving the measIdleConfig and validity criteriafor SCell(s) via the RRC release message, the UE may start performingIDLE mode measurement and checking validity of SCell(s) with thevalidity criteria. The list of SCell(s) of which the UE check validitycan be provided by the network via system information or dedicatedsignalling (e.g. RRC release message).

In step S906, the UE may receive paging message from the network, whilein RRC inactive state.

In step S908, the UE may detect mobile originated (MO) or mobileterminated (MT) data or signaling is triggered.

In step S910, when MO/MT data or signaling is triggered, the UE mayperform RRC connection establishment procedure. In specific, the UE maytransmit a RRC setup request message to the network.

In step S912, the network may provide message including(re-)configuration for SCell(s). The (re-)configuration for SCell mayinclude configuration for SCell and/or PSCell. In specific, the messagemay include radio bearer configuration (e.g. for SRB or DRB addition).Further, the message may include RACH information. The RACH informationmay indicate whether the UE perform RACH procedure toward the determinePSCell and/or SCell. The RACH information may request RACH resourceand/or configuration for the determine PSCell and/or SCell the list ofvalid cell which not belong to the determined PSCell and the list ofdetermined SCell(s). The UE may perform RACH procedure toward thedetermine PSCell and/or SCell if TA of PSCell and/or SCell is not valid.

In step S914, if the UE is able to comply the message, the UE may checkvalidity of SCell(s) associated to the SCell (re-)configuration based onvalidity criteria and identity valid SCell(s) and invalid SCell(s) amongthe SCell(s) associated to the SCell (re-)configuration. Otherwise, theUE perform the actions upon leaving RRC_CONNECTED or re-establishmentprocedure specified in TS 36.331 or TS 38.331.

In step S916, if there is invalid SCell(s), for invalid SCell(s), the UEmay initiate procedure to inform the network that the UE is able tocomply message but not able to apply (re-) configuration because SCellis invalid. When performing the procedure, the UE may send message tothe network where the message includes failure reason/cause (e.g.invalid SCell or invalid PSCell) and the list of invalid SCell(s) in the(re-)configuration. The message may also include the list of validSCell(s). The procedure may be new procedure or existing procedures. Theprocedure may be either failure information procedure or SCG failureinformation. If the invalid SCell is PSCell, the SCG failure informationmay be used. Otherwise, failure information may be used.

Also, existing failure cause/type can be reused. For example, for SCGfailure, existing failure causes/types such as synchReconfigFailure-SCG,randomAccessProblem, rlc-MaxNumRetx, scg-reconfigFailure may be used.For re-using failure cause/type, the UE may determine which cause amongexisting cause will be used for this failure due to invalid SCell.Interaction between RRC layer and lower layers may be made as follows:

-   -   For rlc-MaxNumRetx, RRC layer may request RLC layer to trigger        rlc-MaxNumRetx event and provide the indication for it to RRC        layer. Upon receiving it, RRC layer may perform corresponding        procedure specified in TS 36.331 or TS 38.331.    -   For randomAccessProblem, RRC layer may request MAC layer to        trigger randomAccessProblem event and provide the indication for        it to RRC layer. Upon receiving it, RRC layer may perform        corresponding procedure specified in 3GPP TS 36.331 or TS        38.331.    -   For T310 expiry, RRC layer may request physical layer to trigger        “out-of-sync” event and provide the indication for it to RRC        layer. Upon receiving it, RRC layer may consider T310 is expired        and perform corresponding procedure specified in TS 36.331 or TS        38.331.

In step S918, for valid SCell(s), the UE may perform procedurecorresponding to reception of (re-)configuration (e.g. SCell addition orPSCell addition).

In step S920, the UE may perform synchronization and RA procedure towardvalid SCell(s) if necessary.

In step S922, upon the message, the network may determine new SCell(s)(e.g. new PSCell and/or SCell) and send message including new(re-)configuration for determined new SCell(s) to the UE.

In step S924, upon the message, the UE may perform procedurecorresponding to reception of (re-)configuration (e.g. SCell addition orPSCell addition) and perform RA procedure toward valid SCell(s) ifnecessary.

According to embodiments of the present disclosure, a UE may performfast failure reporting for invalid SCell(s) as soon as identifyinginvalid SCell(s) without waiting of existing failure triggering.Further, the network may perform fast cell setup for CA and DCconfiguration by reducing latency for failure reporting including updateSCell information. That is, a fast cell setup may be achieved byexcluding the invalid cells during the DC setup.

FIG. 10 shows a method for the fast failure reporting for invalidSCell(s) in RRC IDLE mode according to an embodiment of the presentdisclosure. In this embodiment, a UE may be not only a terminal device,but also any types of device operating as wireless device, for example,an integrated access backhaul (IAB) node. Therefore, a UE may bereferred as a wireless device. In this embodiment, a network may be atleast one of base station (BS), gNodeB (gNB) or eNodeB (eNB). In thisembodiment, it may be assumed that the UE supports dual connectivitywith a master node (MN) and a secondary node (SN). The MN may be a MgNBor MeNB, and the SN may be a SgNB or SeNB.

In step S1002, the MN may transmit a RRC connection release message tothe UE with a suspend configuration. The RRC release message may includemeasIdleConfig and validity criteria for SCell(s). The validity criteriamay be provided by the network via system information or dedicatedsignalling (e.g. RRC release message). The valid cell may be a cellsatisfying the following information.

-   -   If RSRP or RSRQ of the cell is greater than certain threshold;        and/or    -   If validity timer is running; and/or    -   If the cell is belong to validity area; and/or    -   If TA of the cell is valid

The MCG SCell configuration may include configuration for SCell(s) inMCG. The

SCG SCell configuration may be called SCG lower layer configuration. TheSCG SCell configuration may include configuration for PSCell and/orSCell(s).

In step S1004, the MN in the network may send message to the SN tosuspend SCG configuration if PSCell associated to the SN is included inthe SCell configuration.

In step S1006, the UE and the SN may keep SCell configuration (e.g. MCGSCell configuration and/or SCG SCell configuration).

In step S1008, the UE may enter into RRC inactive mode upon receivingthe RRC connection release message with suspend configuration.

In step S1010, upon receiving measIdleConfig and validity criteria forSCell(s) in RRC release message, the UE start performing IDLE modemeasurement and checking validity of SCell(s) with the validitycriteria. Upon receiving the RRC release message with suspendconfiguration, the UE may store SCell configuration which the networkconfigure to keep. The list of SCell(s) of which the UE check validitymay be provided by the network via system information or dedicatedsignalling (e.g. RRC release message).

In step S1012, the UE may receive paging message from the network (MN)while in RRC inactive state.

In step S1014, the UE may detect that mobile originated (MO) or mobileterminated (MT) data or signaling is triggered.

In step S1016, the UE may perform RRC resume procedure due to triggeringof MO/MT data or signaling.

In step S1016, the network may provide message including indication toresume the stored SCell configuration. The indication may indicateresume all SCell(s) in the stored SCG lower layer configuration orselectively some SCell(s) in the stored SCG lower layer configuration.For selectively resumption, the list of cell(s) to be resumed may beincluded in the message. The message may be RRC message (e.g. systeminformation or dedicated signaling) or MAC CE.

In step S1020, if the UE is able to comply the message, the UE may checkvalidity of SCell(s) associated to the stored SCell configuration basedon validity criteria and identity valid SCell(s) and invalid SCell(s)among the SCell(s) associated to the stored SCell configuration.Otherwise, the UE perform the actions upon leaving RRC_CONNECTED orre-establishment procedure specified in 3GPP TS 36.331 or TS 38.331.

In step S1022, for invalid SCell(s), the UE may initiate procedure toinform the network the UE is able to comply message but not able toresume the SCell because the SCell is invalid. When performing theprocedure, the UE may send message to the network where the messageincludes failure reason/cause (e.g. invalid SCell) and the list ofinvalid SCell(s) among SCell(s) associated to the stored SCellconfiguration. The message may also include the list of valid SCell(s).

The procedure can be new procedure or existing procedures. For example,the procedure can be either failure information procedure or SCG failureinformation. If the invalid SCell is PSCell, the SCG failure informationmay be used. Otherwise, failure information is used.

Also, existing failure cause/type may be reused.

For example, for SCG failure, existing failure causes/types such assynchReconfigFailure-SCG, randomAccessProblem, rlc-MaxNumRetx,scg-reconfigFailure may be used.

For re-using failure cause/type, the UE determines which cause amongexisting cause will be used for this failure due to invalid SCell.Interaction between RRC layer and lower layers can be made as follows:

-   -   For rlc-MaxNumRetx, RRC layer may equest RLC layer to trigger        rlc-MaxNumRetx event and provide the indication for it to RRC        layer. Upon receiving it, RRC layer may perform corresponding        procedure specified in TS 36.331 or TS 38.331.    -   For randomAccessProblem, RRC layer may request MAC layer to        trigger randomAccessProblem event and provide the indication for        it to RRC layer. Upon receiving it, RRC layer may perform        corresponding procedure specified in TS 36.331 or TS 38.331.    -   For T310 expiry, RRC layer may request physical layer to trigger        “out-of-sync” event and provide the indication for it to RRC        layer. Upon receiving it, RRC layer may consider T310 is expired        and may perform corresponding procedure specified in TS 36.331        or TS 38.331.

The MN may provide a resume message to the SN.

In step S1024, for valid SCell(s), the UE may perform procedurecorresponding to reception of (re-)configuration (e.g. SCell addition orPSCell addition) and perform synchronization and RA procedure towardvalid SCell(s) if necessary.

In step S1026, upon the message sent in step S1022, the network maydetermine new SCell(s) (e.g. new PSCell and/or SCell) and send messageincluding new (re-)configuration for determined new SCell(s) to the UE.The MN in the network may send message to the SN to resume SCGconfiguration if identifying PSCell associated to the SN is valid andresumed in the UE.

In step S1028, the UE may perform RACH procedure toward valid SCell, ifnecessary.

In step S1030, upon the message, the UE may perform procedurecorresponding to reception of (re-)configuration (e.g. SCell addition orPSCell addition) and may perform RA procedure toward valid SCell(s) ifnecessary.

According to embodiments of the present disclosure, a UE may performfast failure reporting for invalid SCell(s) as soon as identifyinginvalid SCell(s) without waiting of existing failure triggering.Further, the network may perform fast cell setup for CA and DCconfiguration by reducing latency for failure reporting including updateSCell information. That is, a fast cell setup may be achieved byexcluding the invalid cells during the DC setup.

According to the prior art, upon receiving RRC resume message, the UEresumes all DRBs. However, UE cannot perform transmission via the DRB ifthe DRB is associated to invalid SCell(s). If the UE resumes radiobearer(s) associated to invalid SCell(s), the UE may performsynchronization or RA procedure or transmission however, it must befailed.

According to another embodiment of the present disclosure, an UE mayperform IDLE mode measurement in RRC inactive mode or RRC IDLE mode. Ifthe UE receives from the network a message including SCell configurationand/or indication to resume all or some SCell(s) in the stored SCellconfiguration and radio bearer configuration, and if the UE can complythe message but identify all or some SCell(s) in the SCell configurationor the stored SCell configuration is (or are) invalid, the UE maysuspend radio bearer(s) associated to invalid SCell(s) or keep radiobearer(s) suspended if have already been suspended. Then, the UE mayinform the network of the list of suspended radio bearer(s) and/or thereason that SCell(s) is invalid. Upon receiving the list of suspendedradio bearer(s) and/or the reason that SCell(s) is invalid, the networkmay provide message including new SCell configuration and/or IE toresume SCell(s) in the stored SCell configuration. Additionally, themessage may include indication/configuration to release or resume thesuspended radio bearer(s).

FIG. 11 shows a method for handling of radio bearer(s) associated toinvalid SCell(s) according to an embodiment of the present disclosure.In this embodiment, the UE may be in either RRC idle mode or RRCinactive mode. In this embodiment, a UE may be not only a terminaldevice, but also any types of device operating as wireless device, forexample, an integrated access backhaul (IAB) node. Therefore, a UE maybe referred as a wireless device. In this embodiment, a network may beat least one of base station (BS), gNodeB (gNB) or eNodeB (eNB). In thisembodiment, it may be assumed that the UE supports dual connectivitywith a master node (MN) and a secondary node (SN). The MN may be a MgNBor MeNB, and the SN may be a SgNB or SeNB.

In step S1102, the network may transmit configuration for idle statemeasurement (measIdleConfig) and validity criteria for SCell(s) to theUE. The validity criteria may be provided by the network via systeminformation or dedicated signaling. The dedicated signaling may be a RRCrelease message. When the UE receives the RRC release message, the UEmay enter into RRC inactive mode.

The valid cell may be a cell which satisfies a condition that RSRP orRSRQ of the cell is greater than certain threshold and/or that validitytimer is running; and/or that the cell is belong to validity area;and/or that TA of the cell is valid.

In step S1104, upon receiving the RRC release message withmeasIdleConfig and validity criteria for SCell(s), the UE may startperforming IDLE mode measurement and checking validity of SCell(s) withthe validity criteria.

The list of SCell(s) of which the UE check validity may be provided bythe network via system information or dedicated signaling (e.g. RRCrelease message).

In step S1106, the UE may receive paging message from the network.

In step S1108, the UE may detect that mobile originated (MO) or mobileterminated (MT) data or signaling is triggered.

In step S1110, the UE may perform RRC connection establishment proceduredue to triggering of MO/MT data or signaling. In specific, the UE maytransmit RRC connection setup message to the network.

In step S1112, the network may provide message including(re-)configuration for SCell(s). The (re-)configuration for SCell mayinclude configuration for SCell and/or PSCell. The message may includeradio bearer configuration (e.g. for SRB or DRB addition). The messagemay include RACH information. The RACH information may indicate whetherthe UE performs RACH procedure toward the determined PSCell and/orSCell. The RACH information may request RACH resource and/orconfiguration for the determined PSCell and/or SCell the list of validcell which not belong to the determined PSCell and the list ofdetermined SCell(s). The UE may perform RACH procedure toward thedetermined PSCell and/or SCell if TA of PSCell and/or SCell is notvalid. The message may include UE identifier used in SN (e.g. RNTI).

In step S1114, if the UE is able to comply the message including the(re-)configuration for SCell(s), the UE may check validity of SCell(s)associated to the (re-)configuration for SCells(s) based on validitycriteria and identifies valid SCell(s) and invalid SCell(s) among theSCell(s) associated to the (re-)configuration for SCells(s). Otherwise,the UE may perform the actions upon leaving RRC_CONNECTED orre-establishment procedure.

In step S1116, the UE may only perform radio bearer configuration forradio bearer(s) associated to valid SCell(s). The UE may not performradio bearer configuration for radio bearer(s) associated to invalidSCell(s). That is, the UE may suspend radio bearer(s) associated toinvalid SCell(s). The radio bearer(s) may be DRB or SRB.

In step S1118, the UE may send message to inform the network of the listof suspended radio bearer(s) and the reason to suspend (i.e. invalidSCell).

In step S1120, for valid SCell(s), the UE may perform procedure relatedto reception of (re-)configuration (e.g. SCell addition or PSCelladdition).

In step S1122, the UE may perform synchronization and RA proceduretoward valid SCell(s) if necessary. The UE may resume radio bearer(s)associated to valid SCell(s).

In step S1124, upon receiving the message, the network may determine newSCell(s) (e.g. new PSCell and/or SCell) and send message including new(re-)configuration for determined new SCell(s) to the UE. The messagemay include new radio bearer configuration to release or resume thesuspended radio bearer(s).

In step S1126, upon receiving the message, the UE may perform procedurerelated to reception of (re-)configuration (e.g. SCell addition orPSCell addition) and may perform RA procedure toward valid SCell(s) ifnecessary.

According to embodiments of the present disclosure, a UE may performefficient handling of radio bearer(s) associated to invalid SCell(s). Inspecific, fast cell setup may be achieved by excluding the invalid cellsduring the DC setup.

Further, according to embodiments of the present disclosure, it may bebeneficial to prevent unnecessary triggering of procedure such assynchronization, Random access and transmission due to trial oftransmission or reception via radio bearer(s) associated to invalidSCell(s).

FIG. 12 shows a method for handling of radio bearer(s) associated toinvalid SCell(s) according to an embodiment of the present disclosure.In this embodiment, the UE may be in either RRC idle mode or RRCinactive mode. In this embodiment, a UE may be not only a terminaldevice, but also any types of device operating as wireless device, forexample, an integrated access backhaul (IAB) node. Therefore, a UE maybe referred as a wireless device. In this embodiment, a network may beat least one of base station (BS), gNodeB (gNB) or eNodeB (eNB). In thisembodiment, it may be assumed that the UE supports dual connectivitywith a master node (MN) and a secondary node (SN). The MN may be a MgNBor MeNB, and the SN may be a SgNB or SeNB.

In this embodiment, as a beginning condition, it may be assumed that aUE performed a mobility procedure. That is, the UE may perform handoverprocedure with the network, and may be handed over to the MN.

In step S1202, the MN may transmit a RRC connection release message tothe UE with a suspend configuration. The RRC release message may includemeasIdleConfig and validity criteria for SCell(s). The validity criteriamay be provided by the network via system information or dedicatedsignalling (e.g. RRC release message). The valid cell may be a cellsatisfying the following information.

-   -   If RSRP or RSRQ of the cell is greater than certain threshold;        and/or    -   If validity timer is running; and/or    -   If the cell is belong to validity area; and/or    -   If TA of the cell is valid

The MCG SCell configuration may include configuration for SCell(s) inMCG. The SCG SCell configuration may be called SCG lower layerconfiguration. The SCG SCell configuration may include configuration forPSCell and/or SCell(s).

In step S1204, the MN in the network may send message to the SN tosuspend SCG configuration if PSCell associated to the SN is included inthe SCell configuration.

In step S1206, the UE and the SN may keep SCell configuration (e.g. MCGSCell configuration and/or SCG SCell configuration).

In step S1208, the UE may enter into RRC inactive mode upon receivingthe RRC connection release message with suspend configuration.

In step S1210, upon receiving measIdleConfig and validity criteria forSCell(s) in RRC release message, the UE may start performing IDLE modemeasurement and checking validity of SCell(s) with the validitycriteria. The list of SCell(s) of which the UE check validity may beprovided by the network via system information or dedicated signalling(e.g. RRC release message).

In step S1212, the UE may receive paging from the network, while stayingin RRC inactive state.

In step S1214, the UE may detect that mobile originated (MO) or mobileterminated (MT) data or signaling is triggered.

In step S1216, the UE may perform RRC resume procedure due to triggeringof MO/MT data or signaling.

In step S1218, the network may provide message including indication toresume the stored SCell configuration. The indication may be to resumeall SCell(s) in the stored SCG lower layer configuration or selectivelyresume some SCell(s) in the stored SCG lower layer configuration. Forselective resumption, the list of cell(s) to be resumed may be includedin the message. The message may be RRC message (e.g. system informationor dedicated signalling) or MAC CE.

In step S1220, if the UE is able to comply the message including theindication to resume the stored SCell configuration, the UE may checkvalidity of SCell(s) associated to the stored SCell configuration basedon validity criteria and identify valid SCell(s) and invalid SCell(s)among the SCell(s) associated to the stored SCell configuration.Otherwise, the UE may perform the actions upon leaving RRC_CONNECTED orre-establishment procedure.

In step S1222, the UE may only perform radio bearer configuration forradio bearer(s) associated to valid SCell(s) and may not perform radiobearer configuration for radio bearer(s) associated to invalid SCell(s).That is, the UE may suspend radio bearer(s) associated to invalidSCell(s). The radio bearer(s) may be DRB or SRB.

According to an example of the embodiment, if PSCell in the cell groupconfiguration is invalid, the UE may suspend all radio bearer(s)associated to the cell group, or the UE may keep the radio bearer(s)suspended if the radio bearers have already been suspended.

If PSCell in the cell group configuration is valid but there is a radiobearer to which no SCell associated is invalid, the UE may suspend theradio bearer(s), or the UE may keep the radio bearer(s) suspended if theradio bearer have already been suspended.

In step S1224, the UE may send message to inform the network the list ofsuspended radio bearer(s) and the reason to suspend (i.e. invalidSCell).

In step S1226, for valid SCell(s), the UE may perform procedure relatedto reception of (re-)configuration (e.g. SCell addition or PSCelladdition).

In step S1228, the UE may perform synchronization and RA proceduretoward valid SCell(s) if necessary.

In step S1230, upon receiving the message, the network may determine newSCell(s) (e.g. new PSCell and/or SCell) and send message including new(re-)configuration for determined new SCell(s) to the UE. The messagemay include new radio bearer configuration to release or resume thesuspended radio bearer(s). The MN in the network may send message to theSN to resume SCG configuration if identifying PSCell associated to theSN is valid and resumed in the UE.

In step S1232, upon receiving the message, the UE may perform procedurerelated to reception of (re-)configuration (e.g. SCell addition orPSCell addition) and may perform RA procedure toward valid SCell(s) ifnecessary.

According to embodiments of the present disclosure, a UE may performefficient handling of radio bearer(s) associated to invalid SCell(s). Inspecific, fast cell setup may be achieved by excluding the invalid cellsduring the DC setup.

According to embodiments of the present disclosure, it may be beneficialto prevent unnecessary triggering of procedure such as synchronization,Random access and transmission due to trial of transmission or receptionvia radio bearer(s) associated to invalid SCell(s).

FIG. 13 shows more detailed wireless device to implement an embodimentof the present disclosure. The present disclosure described above forwireless device side may be applied to this embodiment.

A wireless device includes a processor 1310, a power management module1311, a battery 1312, a display 1313, a keypad 1314, a subscriberidentification module (SIM) card 1315, a memory 1320, a transceiver1330, one or more antennas 1331, a speaker 1340, and a microphone 1341.

The processor 1310 may be configured to implement proposed functions,procedures and/or methods described in this description. Layers of theradio interface protocol may be implemented in the processor 1310. Theprocessor 1310 may include ASIC, other chipset, logic circuit and/ordata processing device. The processor 1310 may be an applicationprocessor (AP). The processor 1310 may include at least one of a digitalsignal processor (DSP), a central processing unit (CPU), a graphicsprocessing unit (GPU), a modem (modulator and demodulator). An exampleof the processor 1310 may be found in SNAPDRAGON™ series of processorsmade by Qualcomm®, EXYNOS™ series of processors made by Samsung®, Aseries of processors made by Apple®, HELIO™ series of processors made byMediaTek®, ATOMTM series of processors made by Intel® or a correspondingnext generation processor.

According to an embodiment of the present disclosure, the processor 1310may be configured to receive a cell group configuration including a listof cells. The cell group configuration may further include a measurementconfiguration for the measurement.

The processor 1310 may be configured to perform measurement on thecells. The measurement may be performed while the wireless device is inradio resource control (RRC) inactive state or a RRC idle state.

The processor 1310 may be configured to identify at least one invalidcell among the cells included in the cell group configuration based onat least one of a result of the measurement. The invalid cells may beidentified based on a channel quality, a predefined validity area,timing advance (TA), or validity timer.

Further, the processor 1310 may be further configured to suspend a radiobearer which is related to the identified invalid cell. The suspendingthe radio bearer may bes performed when all cells related to the radiobearer are invalid. In this case, the all cells related to the radiobearer may be a secondary cell (SCell). Meanwhile, the suspending theradio bearer may be performed when at least one cell related to theradio bearer is invalid. In this case, the at least one cell related tothe radio bearer may be a primary secondary cell (PSCell)

The processor 1310 may be configured to report information on theidentified invalid cell. The information on the identified invalid cellmay include information of the suspended radio bearer.

According to embodiments of the present disclosure, a UE may performfast failure reporting for invalid SCell(s) as soon as identifyinginvalid SCell(s) without waiting of existing failure triggering.Further, the network may perform fast cell setup for CA and DCconfiguration by reducing latency for failure reporting including updateSCell information.

The power management module 1311 manages power for the processor 1310and/or the transceiver 1330. The battery 1312 supplies power to thepower management module 1311. The display 1313 outputs results processedby the processor 1310. The keypad 1314 receives inputs to be used by theprocessor 1310. The keypad 1314 may be shown on the display 1313. TheSIM card 1315 is an integrated circuit that is intended to securelystore the international mobile subscriber identity (IMSI) number and itsrelated key, which are used to identify and authenticate subscribers onmobile telephony devices (such as mobile phones and computers). It isalso possible to store contact information on many SIM cards.

The memory 1320 is operatively coupled with the processor 1310 andstores a variety of information to operate the processor 1310. Thememory 1320 may include ROM, RAM, flash memory, memory card, storagemedium and/or other storage device. When the embodiments are implementedin software, the techniques described herein can be implemented withmodules (e.g., procedures, functions, and so on) that perform thefunctions described herein. The modules can be stored in the memory 1320and executed by the processor 1310. The memory 1320 can be implementedwithin the processor 1310 or external to the processor 1310 in whichcase those can be communicatively coupled to the processor 1310 viavarious means as is known in the art.

The transceiver 1330 is operatively coupled with the processor 1310, andtransmits and/or receives a radio signal. The transceiver 1330 includesa transmitter and a receiver. The transceiver 1330 may include basebandcircuitry to process radio frequency signals. The transceiver 1330controls the one or more antennas 1331 to transmit and/or receive aradio signal.

The speaker 1340 outputs sound-related results processed by theprocessor 1310. The microphone 1341 receives sound-related inputs to beused by the processor 1310.

The embodiments of the disclosure may be applied to various futuretechnologies, such as AI, robots, autonomous-driving/self-drivingvehicles, and/or extended reality (XR).

AI refers to artificial intelligence and/or the field of studyingmethodology for making it. Machine learning is a field of studyingmethodologies that define and solve various problems dealt with in AI.Machine learning may be defined as an algorithm that enhances theperformance of a task through a steady experience with any task.

An artificial neural network (ANN) is a model used in machine learning.It can mean a whole model of problem-solving ability, consisting ofartificial neurons (nodes) that form a network of synapses. An ANN canbe defined by a connection pattern between neurons in different layers,a learning process for updating model parameters, and/or an activationfunction for generating an output value. An ANN may include an inputlayer, an output layer, and optionally one or more hidden layers. Eachlayer may contain one or more neurons, and an ANN may include a synapsethat links neurons to neurons. In an ANN, each neuron can output asummation of the activation function for input signals, weights, anddeflections input through the synapse. Model parameters are parametersdetermined through learning, including deflection of neurons and/orweights of synaptic connections. The hyper-parameter means a parameterto be set in the machine learning algorithm before learning, andincludes a learning rate, a repetition number, a mini batch size, aninitialization function, etc. The objective of the ANN learning can beseen as determining the model parameters that minimize the lossfunction. The loss function can be used as an index to determine optimalmodel parameters in learning process of ANN.

Machine learning can be divided into supervised learning, unsupervisedlearning, and reinforcement learning, depending on the learning method.Supervised learning is a method of learning ANN with labels given tolearning data. Labels are the answers (or result values) that ANN mustinfer when learning data is input to ANN. Unsupervised learning can meana method of learning ANN without labels given to learning data.Reinforcement learning can mean a learning method in which an agentdefined in an environment learns to select a behavior and/or sequence ofactions that maximizes cumulative compensation in each state.

Machine learning, which is implemented as a deep neural network (DNN)that includes multiple hidden layers among ANN, is also called deeplearning. Deep learning is part of machine learning. In the following,machine learning is used to mean deep learning.

A robot can mean a machine that automatically processes or operates agiven task by its own abilities. In particular, a robot having afunction of recognizing the environment and performingself-determination and operation can be referred to as an intelligentrobot. Robots can be classified into industrial, medical, household,military, etc., depending on the purpose and field of use. The robot mayinclude a driving unit including an actuator and/or a motor to performvarious physical operations such as moving a robot joint. In addition,the movable robot may include a wheel, a break, a propeller, etc., in adriving unit, and can travel on the ground or fly in the air through thedriving unit.

The autonomous-driving refers to a technique of self-driving, and anautonomous vehicle refers to a vehicle that travels without a user'soperation or with a minimum operation of a user. For example,autonomous-driving may include techniques for maintaining a lane whiledriving, techniques for automatically controlling speed such as adaptivecruise control, techniques for automatically traveling along apredetermined route, and techniques for traveling by setting a routeautomatically when a destination is set. The autonomous vehicle mayinclude a vehicle having only an internal combustion engine, a hybridvehicle having an internal combustion engine and an electric motortogether, and an electric vehicle having only an electric motor, and mayinclude not only an automobile but also a train, a motorcycle, etc. Theautonomous vehicle can be regarded as a robot having an autonomousdriving function.

XR are collectively referred to as VR, AR, and MR. VR technologyprovides real-world objects and/or backgrounds only as computer graphic(CG) images, AR technology provides CG images that is virtually createdon real object images, and MR technology is a computer graphicstechnology that mixes and combines virtual objects in the real world. MRtechnology is similar to AR technology in that it shows real and virtualobjects together. However, in the AR technology, the virtual object isused as a complement to the real object, whereas in the MR technology,the virtual object and the real object are used in an equal manner. XRtechnology can be applied to HMD, head-up display (HUD), mobile phone,tablet PC, laptop, desktop, TV, digital signage. A device to which theXR technology is applied may be referred to as an XR device.

FIG. 14 shows an example of an AI device to which the technical featuresof the disclosure can be applied.

The AI device 1400 may be implemented as a stationary device or a mobiledevice, such as a TV, a projector, a mobile phone, a smartphone, adesktop computer, a notebook, a digital broadcasting terminal, a PDA, aPMP, a navigation device, a tablet PC, a wearable device, a set-top box(STB), a digital multimedia broadcasting (DMB) receiver, a radio, awashing machine, a refrigerator, a digital signage, a robot, a vehicle,etc.

Referring to FIG. 14, the AI device 1400 may include a communicationpart 1410, an input part 1420, a learning processor 1430, a sensing part1440, an output part 1450, a memory 1460, and a processor 1470.

The communication part 1410 can transmit and/or receive data to and/orfrom external devices such as the AI devices and the AI server usingwire and/or wireless communication technology. For example, thecommunication part 1410 can transmit and/or receive sensor information,a user input, a learning model, and a control signal with externaldevices. The communication technology used by the communication part1410 may include a global system for mobile communication (GSM), a codedivision multiple access (CDMA), an LTE/LTE-A, a 5G, a WLAN, a Wi-Fi,Bluetooth™, radio frequency identification (RFID), infrared dataassociation (IrDA), ZigBee, and/or near field communication (NFC).

The input part 1420 can acquire various kinds of data. The input part1420 may include a camera for inputting a video signal, a microphone forreceiving an audio signal, and a user input part for receivinginformation from a user. A camera and/or a microphone may be treated asa sensor, and a signal obtained from a camera and/or a microphone may bereferred to as sensing data and/or sensor information. The input part1420 can acquire input data to be used when acquiring an output usinglearning data and a learning model for model learning. The input part1420 may obtain raw input data, in which case the processor 1470 or thelearning processor 1430 may extract input features by preprocessing theinput data.

The learning processor 1430 may learn a model composed of an ANN usinglearning data. The learned ANN can be referred to as a learning model.The learning model can be used to infer result values for new input datarather than learning data, and the inferred values can be used as abasis for determining which actions to perform. The learning processor1430 may perform AI processing together with the learning processor ofthe AI server. The learning processor 1430 may include a memoryintegrated and/or implemented in the AI device 1400. Alternatively, thelearning processor 1430 may be implemented using the memory 1460, anexternal memory directly coupled to the AI device 1400, and/or a memorymaintained in an external device.

The sensing part 1440 may acquire at least one of internal informationof the AI device 1400, environment information of the AI device 1400,and/or the user information using various sensors. The sensors includedin the sensing part 1440 may include a proximity sensor, an illuminancesensor, an acceleration sensor, a magnetic sensor, a gyro sensor, aninertial sensor, an RGB sensor, an IR sensor, a fingerprint recognitionsensor, an ultrasonic sensor, an optical sensor, a microphone, a lightdetection and ranging (LIDAR), and/or a radar.

The output part 1450 may generate an output related to visual, auditory,tactile, etc. The output part 1450 may include a display unit foroutputting visual information, a speaker for outputting auditoryinformation, and/or a haptic module for outputting tactile information.

The memory 1460 may store data that supports various functions of the AIdevice 1400. For example, the memory 1460 may store input data acquiredby the input part 1420, learning data, a learning model, a learninghistory, etc.

The processor 1470 may determine at least one executable operation ofthe AI device 1400 based on information determined and/or generatedusing a data analysis algorithm and/or a machine learning algorithm. Theprocessor 1470 may then control the components of the AI device 1400 toperform the determined operation. The processor 1470 may request,retrieve, receive, and/or utilize data in the learning processor 1430and/or the memory 1460, and may control the components of the AI device1400 to execute the predicted operation and/or the operation determinedto be desirable among the at least one executable operation. Theprocessor 1470 may generate a control signal for controlling theexternal device, and may transmit the generated control signal to theexternal device, when the external device needs to be linked to performthe determined operation. The processor 1470 may obtain the intentioninformation for the user input and determine the user's requirementsbased on the obtained intention information. The processor 1470 may useat least one of a speech-to-text (STT) engine for converting speechinput into a text string and/or a natural language processing (NLP)engine for acquiring intention information of a natural language, toobtain the intention information corresponding to the user input. Atleast one of the STT engine and/or the NLP engine may be configured asan ANN, at least a part of which is learned according to a machinelearning algorithm. At least one of the STT engine and/or the NLP enginemay be learned by the learning processor 1430 and/or learned by thelearning processor of the AI server, and/or learned by their distributedprocessing. The processor 1470 may collect history information includingthe operation contents of the AI device 1400 and/or the user's feedbackon the operation, etc. The processor 1470 may store the collectedhistory information in the memory 1460 and/or the learning processor1430, and/or transmit to an external device such as the AI server. Thecollected history information can be used to update the learning model.The processor 1470 may control at least some of the components of AIdevice 1400 to drive an application program stored in memory 1460.Furthermore, the processor 1470 may operate two or more of thecomponents included in the AI device 1400 in combination with each otherfor driving the application program.

FIG. 15 shows an example of an AI system to which the technical featuresof the present disclosure can be applied.

Referring to FIG. 15, in the AI system, at least one of an AI server1520, a robot 1510 a , an autonomous vehicle 1510 b , an XR device 1510c , a smartphone 1510 d and/or a home appliance 1510 e is connected to acloud network 1500. The robot 1510 a , the autonomous vehicle 1510 b ,the XR device 1510 c , the smartphone 1510 d , and/or the home appliance1510 e to which the AI technology is applied may be referred to as AIdevices 1510 a to 1510 e.

The cloud network 1500 may refer to a network that forms part of a cloudcomputing infrastructure and/or resides in a cloud computinginfrastructure. The cloud network 1500 may be configured using a 3Gnetwork, a 4G or LTE network, and/or a 5G network. That is, each of thedevices 1510 a to 1510 e and 1520 consisting the AI system may beconnected to each other through the cloud network 1500. In particular,each of the devices 1510 a to 1510 e and 1520 may communicate with eachother through a base station, but may directly communicate with eachother without using a base station.

The AI server 1520 may include a server for performing AI processing anda server for performing operations on big data. The AI server 1520 isconnected to at least one or more of AI devices constituting the AIsystem, i.e. the robot 1510 a , the autonomous vehicle 1510 b , the XRdevice 1510 c , the smartphone 1510 d and/or the home appliance 1510 ethrough the cloud network 1500, and may assist at least some AIprocessing of the connected AI devices 1510 a to 1510 e . The AI server1520 can learn the ANN according to the machine learning algorithm onbehalf of the AI devices 1510 a to 1510 e , and can directly store thelearning models and/or transmit them to the AI devices 1510 a to 1510 e. The AI server 1520 may receive the input data from the AI devices 1510a to 1510 e , infer the result value with respect to the received inputdata using the learning model, generate a response and/or a controlcommand based on the inferred result value, and transmit the generateddata to the AI devices 1510 a to 1510 e . Alternatively, the AI devices1510 a to 1510 e may directly infer a result value for the input datausing a learning model, and generate a response and/or a control commandbased on the inferred result value.

Various embodiments of the AI devices 1510 a to 1510 e to which thetechnical features of the present disclosure can be applied will bedescribed. The AI devices 1510 a to 1510 e shown in FIG. 15 can be seenas specific embodiments of the AI device 1400 shown in FIG. 14.

In view of the exemplary systems described herein, methodologies thatmay be implemented in accordance with the disclosed subject matter havebeen described with reference to several flow diagrams. While forpurposed of simplicity, the methodologies are shown and described as aseries of steps or blocks, it is to be understood and appreciated thatthe claimed subject matter is not limited by the order of the steps orblocks, as some steps may occur in different orders or concurrently withother steps from what is depicted and described herein. Moreover, oneskilled in the art would understand that the steps illustrated in theflow diagram are not exclusive and other steps may be included or one ormore of the steps in the example flow diagram may be deleted withoutaffecting the scope of the present disclosure.

Claims in the present description can be combined in a various way. Forinstance, technical features in method claims of the present descriptioncan be combined to be implemented or performed in an apparatus, andtechnical features in apparatus claims can be combined to be implementedor performed in a method. Further, technical features in method claim(s)and apparatus claim(s) can be combined to be implemented or performed inan apparatus. Further, technical features in method claim(s) andapparatus claim(s) can be combined to be implemented or performed in amethod. Other implementations are within the scope of the followingclaims.

What is claimed is:
 1. A method performed by a wireless device in awireless communication system, the method comprising: receiving a cellgroup configuration including a list of cells; performing measurement onthe cells; identifying at least one invalid cell among the cellsincluded in the cell group configuration based on a result of themeasurement; reporting information on the identified invalid cell. 2.The method of claim 1, wherein the invalid cells are identified based ona channel quality, a predefined validity area, timing advance (TA), orvalidity timer.
 3. The method of claim 1, wherein the cell groupconfiguration further includes a measurement configuration for themeasurement.
 4. The method of claim 1, wherein the measurement isperformed while the wireless device is in radio resource control (RRC)inactive state or a RRC idle state.
 5. The method of claim 1, furthercomprising: suspending a radio bearer which is related to the identifiedinvalid cell.
 6. The method of claim 5, wherein the information on theidentified invalid cell includes information of the suspended radiobearer.
 7. The method of claim 5, wherein the suspending the radiobearer is performed when all cells related to the radio bearer areinvalid.
 8. The method of claim 7, wherein the all cells related to theradio bearer is a secondary cell (SCell).
 9. The method of claim 5,wherein the suspending the radio bearer is performed when at least onecell related to the radio bearer is invalid.
 10. The method of claim 9,wherein the at least one cell related to the radio bearer is a primarysecondary cell (PSCell).
 11. The method of claim 1, wherein the wirelessdevice communicates with at least one of a mobile terminal, a network orautonomous vehicles other than the wireless device.
 12. A wirelessdevice in a wireless communication system, the wireless devicecomprising: a memory; a transceiver; and a processor, operably coupledto the memory and the transceiver, and configured to: control thetransceiver to receive a cell group configuration including a list ofcells; perform measurement on the cells; identify at least one invalidcell among the cells included in the cell group configuration based on aresult of the measurement; control the transceiver to report informationon the identified invalid cell.
 13. The wireless device of claim 12,wherein the invalid cells are identified based on a channel quality, apredefined validity area, timing advance (TA), or validity timer. 14.The wireless device of claim 12, wherein the cell group configurationfurther includes a measurement configuration for the measurement. 15.The wireless device of claim 12, wherein the measurement is performedwhile the wireless device is in radio resource control (RRC) inactivestate or a RRC idle state